Lighting device and projector

1. A lighting device comprising a lamp unit having a light source lamp and a reflector for reflecting light emitted from the light source lamp, the lighting device further comprising: a plurality of the lamp units arrayed adjacent to one another; wherein the reflector of each lamp unit has a shape obtained through cutting a concave surface of reflection on at least one end adjoining to another lamp unit by a plane substantially perpendicular to a direction of the array of the lamp units, the reflector has a shape obtained through cutting both ends of the concave surface of reflection by the plane substantially perpendicular to the direction of the array of the lamp units, and a distance between both cut faces is approximately half a diameter of an opening of the concave surface of reflection.

2. A lighting device in accordance with claim 1, wherein the plurality of lamp units are arrayed in one direction substantially perpendicular to the optical axis of the light source lamp.

3. A lighting device in accordance with claim 1, wherein the plurality of lamp units are arrayed in two directions substantially perpendicular to the optical axis of the light source lamp.

4. A lighting device in accordance with claim 1, wherein the reflectors included in the plurality of lamp units are optically integrated with one another.

5. A lighting device in accordance with claim 1, the lighting device further comprising: a control circuit for selectively turning on any of the light source lamps included in the plurality of lamp units.

6. A lighting device in accordance with claim 1, wherein the light source lamps included in the plurality of lamp units emit respective light of different wavelength distribution characteristics.

7. A lighting device in accordance with claim 1, the lighting device further comprising: an integrator optical system having a first lens plate including a plurality of lenses and a second lens plate including a plurality of lenses, wherein the first lens plate spatially divides the light emitted from the light source lamp by the plurality of lenses included therein to produce a plurality of intermediate light fluxes, which are focused as secondary light source images in the vicinity of entrance planes of the plurality of lenses included in the second lens plate, output via the plurality of lenses included in the second lens plate, and superposed on a predetermined illumination area.

8. A lighting device in accordance with claim 7, the lighting device further comprising: polarizing means for converting light fluxes output from the second lens plate to light fluxes of a single polarization type having identical polarizing directions and outputting the light fluxes of the single polarization type, the polarizing means comprising: polarization separating means for separating the light fluxes output from the second lens plate into light fluxes of two polarization types having different polarizing directions; and polarization converting means for converting the polarizing direction of one of the light fluxes of the two polarization types obtained by the polarization separating means to the polarizing direction of the other of the light fluxes of the two polarization types, wherein the predetermined illumination area is illuminated with the polarized light fluxes of the single type having identical polarizing directions obtained by the polarizing means.

9. A projector comprising: a lighting device in accordance with claim 1; modulation means for modulating light emitted from the lighting device responsive to image information; and a projection optical system for projecting a modulated light flux obtained by the modulation means onto a projection plane.

10. A projector in accordance with claim 9, further comprising: color separation means for separating the light emitted from the lighting device into at least two color light fluxes; a plurality of the modulation means for modulating the respective color light fluxes separated by the color separation means; and color combining means for combining the color light fluxes modulated by the plurality of modulation means, wherein a composite light flux obtained by the color combining means is projected on the projection plane via the projection optical system.

11. A lighting device for illuminating an illumination area of a substantially rectangular shape having sides parallel to either of a first direction and a second direction which are substantially perpendicular to each other, the lighting device comprising: a light source; a first lens plate having a plurality of small lenses for dividing a light flux emitted from the light source into a plurality of partial light fluxes and condensing the plurality of partial light fluxes; a second lens plate having a plurality of small lenses on which the plurality of partial light fluxes are incident; polarizing means comprising polarization separating means for separating each of the plurality of partial light fluxes output from the second lens plate into light fluxes of two polarization types having different polarizing directions, and polarization converting means for converting the polarizing direction of one of the light fluxes of the two polarization types obtained by the polarization separating means to the polarizing direction of the other of the light fluxes of the two polarization types, the polarizing means thereby converting the plurality of partial light fluxes to plural light fluxes of a single polarization type having substantially identical polarizing directions and outputting the plural light fluxes of the single polarization type; and superposing means for superposing the plural polarized light fluxes output from the polarizing means to illuminate the illumination area, wherein the polarization separating means is arranged to cause the light fluxes of two polarization types to be spatially separated along the first direction of the illumination area, wherein each the small lens of the first lens plate has a substantially rectangular shape when projected on a plane perpendicular to a central optical axis of the each small lens, the substantially rectangular shape having an aspect ratio that is virtually equal to an aspect ratio of the illumination area, the plurality of partial light fluxes output from the small lenses being incident on corresponding small lenses of the second lens plate, wherein each the small lens of the second lens plate has a substantially rectangular shape when projected on a plane perpendicular to a central optical axis of the each small lens, the substantially rectangular shape having an aspect ratio that is smaller than the aspect ratio of the illumination area, and wherein the aspect ratio is defined by a ratio of a length of the side parallel to the second direction to a length of the side parallel to the first direction.

12. A lighting device in accordance with claim 11, wherein the light source comprises a plurality of lamp units arrayed in the second direction, each the lamp unit having a light source lamp and a reflector for reflecting light emitted from the light source lamp.

13. A lighting device in accordance with claim 11, wherein the aspect ratio of the each small lens of the second lens plate is approximately 1/2.

14. A lighting device in accordance with claim 11, wherein the plurality of small lenses included in the second lens plate are arranged in a plurality of rows along the second direction, and dimensions along the second direction of the small lenses in each row are reduced with their distances from a center position of the light flux emitted from the light source.

15. A lighting device in accordance with claim 12, wherein the reflector of each lamp unit has a shape obtained through cutting a concave surface of reflection on at least one end adjoining to another lamp unit by a plane substantially perpendicular to a direction of the array of the lamp units.

16. A projector comprising: a lighting device in accordance with claim 11; modulation means for modulating light emitted from the lighting device responsive to image information; and a projection optical system for projecting a modulated light flux obtained by the modulation means onto a projection plane.

17. A projector in accordance with claim 16, further comprising: color separation means for separating the light emitted from the lighting device into at least two color light fluxes; a plurality of the modulation means for modulating the respective color light fluxes separated by the color separation means; and color combining means for combining the color light fluxes modulated by the plurality of modulation means, wherein a composite light flux obtained by the color combining means is projected on the projection plane via the projection optical system.

18. A lighting device in accordance with claim 12, wherein the aspect ration of the each small lens of the second lens plate is approximately 1/2.

19. A lighting device in accordance with claim 12, wherein the plurality of small lenses included in the second lens plate are arranged in a plurality of rows along the second direction, and dimensions along the second direction of the small lenses in each row are reduced with their distances from a center position of the light flux emitted from the light source.

20. A projector comprising: a lighting device in accordance with claim 12; modulation means for modulating light emitted from the lighting device responsive to image information; and a projection optical system for projecting a modulated light flux obtained by the modulation means onto a projection plane.

21. A projector in accordance with claim 20, further comprising: color separation means for separating the light emitted from the lighting device into at least two color light fluxes; a plurality of the modulation means for modulating the respective color light fluxes separated by the color separation means; and color combining means for combining the color light fluxes modulated by the plurality of modulation means, wherein a composite light flux obtained by the color combining means is projected on the projection plane via the projection optical system.